Land Use

WMS-Accessible Land Use Data

WMS offers an option to download NLCD land use data for anywhere in the United States and CORINE data for anywhere in Europe using the Get Data or the Get Data from Map tools. This is the recommended method to get land use data into WMS unless you have other land use sources that may be more recent or better quality.

USGS National Map Viewer

The national map viewer has several land use data sources (impervious areas, land use types, vegetation types, etc.) from various dates. All land use sources are in GeoTIFF format and can be read into WMS as raster GIS data and then converted to a land use grid. The land use grid can the be used to compute composite runoff parameters such as Curve Number and to assign parameters to 2D grids for distributed hydrology.

NRCS - State Soil Geographic (STATSGO) Database

The United States Department of Agriculture (USDA) supports the Natural Resources Conservation Service (NRCS). A website they have developed is the National Cartography and Geospatial Center (NCGC). Supplied on this website are numerous links and descriptions of geospatial datasets. Through these links it is possible to acquire soil type data maps from the two main soils databases; STATSGO, and SSURGO.

Web Soil Survey

Web Soil Survey is a data request site supported by the United Sates Department of Agriculture (USDA) through the Natural Resources Conservation Service (NRCS). From Web Soil Survey you can place orders requesting certain soil survey maps. It specifically caters to only soil data needs.

Geospatial Data Gateway

The Geospatial Data Gateway is a site sponsored by the United States Department of Agriculture (USDA) through the Natural Resources Conservation Service (NRCS). Numerous databases are available by means of the Geospatial Data Gateway including; transportation, census, land use / land cover, soil type, ortho imagery, elevation, and topographic maps. Description below applies to SSURGO soil type data only.

Land Use Overview

Of the many methods to estimate infiltration, the NRCS Curve Number (CN) method is one that is commonly used. For watersheds with multiple soil types and land uses, a composite CN (CCN) must be calculated to estimate the infiltration losses. The USDA/NRCS supplies tables so that a CCN can be determined from soil type, land use, moisture condition, and hydrologic condition. In hydrology, land use (also known as cover crop or land cover) refers to the way in which the land is being used and/or its condition. Land uses can be urban or agricultural/rural. Examples of these include streets, industrial areas, commercial areas, row crops, meadows, pasture/range and woods.

Land use data for the Provo, Utah region, displayed in ArcView.

Soil Type Overview

For watersheds with multiple soil types and land uses, a composite CN (CCN) must be calculated to estimate the infiltration losses. The NRCS (part of the USDA) supplies tables so that a CCN can be determined from soil type, land use, moisture condition, and hydrologic condition. In hydrology, soil type can be classified in many ways. The USDA classifies them according to their infiltration rate and are referred to as either A, B, C, or D soils. Soil type A has a high infiltration rate whereas soil type D usually consists of clays that are nearly impermeable (low infiltration) and produce higher volumes of runoff.